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The first 150 words of the full text of this article appear below. Key points Coronary artery disease accounts for >30% ofdeaths in Western society. The diagnosis of myocardial infarctionshould be qualified by size, causation and time from occurrence. Mortalityis reduced by immediate or primary percutaneouscoronary intervention or thrombolysis within the first 24 hof onset of ST-segment elevation myocardial infarction. Strategiesto reduce platelet activation (glycoprotein IIb/IIIa receptorantagonists, or clopidogrel) are now recommended in the treatmentof high-risk non-ST-segment myocardial infarction/unstable angina. Elevatedserum troponins may be the result of non-ischaemic myocardialdamage, especially in critical illness.
Pathophysiology
Changes in the definition of terms relating to the diagnosisof myocardial infarction (MI) have evolved by better understandingof the pathophysiology culminating in the new term of acutecoronary syndrome (ACS). Figure 1 illustrates the processesthat occur in the development of an acute coronary event. 相似文献
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Ali Ihya Karaman Omür Polat Tamer Büyükyilmaz 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):327-330
Retention is a major part of orthodontic treatment, not an optional secondary protocol. In recent years, studies investigating dentofacial changes during and after the growth period have led most clinicians to use fixed retention appliances after treatment. Fixed retainers can be attached to the teeth directly or indirectly. We present a practical, indirect method for bonding fixed retainers, using Sondhi Rapid-set Indirect Bonding Adhesive (3M Unitek, Monrovia, Calif). 相似文献
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The detergent-soluble extract of rat ovary plasma membranes contained a Gs protein of about 100 kDa as shown by its elution behavior on a Bio Gel A-1.5m column. However, the cell membranes exposed to hCG (37° C, 15 min) contained in addition a higher molecular weight Gs protein complex of 300 kDa comprised of human chorionic gonadotropin (hCG) receptor (hCGR) and Gs. The complex bound with an affinity column of GTP-Sepharose and could be released with Gpp(NH)p and GTP inhibited this binding. The presence of the hCGR in the complex was shown by its binding to 125I-hCG. Furthermore, GTP inhibited the binding of hCG to the complex. These results indicate the presence of hCGR and Gs protein complex in the hCG-treated membranes. hCGR and Gs protein were individually purified and reconstituted into phospholipid vesicles. The protein-phospholipid vesicles showed saturation kinetics of binding of 125I-hCG and 3H-Gpp(NH)p. Incubation of phospholipid vesicles with hCG resulted in a 2–3-fold increase in the binding of 3H-Gpp(NH)p and GTPase activity. Activation of Gs protein was dependent on the length of incubation and the hormone concentration. Deglycosylated hCG was about 10 times less potent than hCG suggesting a role of carbohydrates of hCG in inducing hCG-Gs protein interactions. The data with the in vitro reconstitution system rule out the involvement of a carbohydrate-binding lectin in the function of the hormone. 相似文献
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Ibrahim Ercan Burak Omür Cakir Tülay Ba?ak Eltaf Ay?a Ozbal Atilla Sahin Gürhan Balci Suat Turgut 《Otolaryngology--head and neck surgery》2006,134(5):751-755
OBJECTIVE: The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels. STUDY DESIGN: Preclinical animal study. SETTING: Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples. RESULTS: There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level. CONCLUSIONS: These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence. 相似文献
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Ibrahim Ercan Burak Omür Cakir Tulin Sentürk Uzel Damlanur Sakiz Cetin Karaca Suat Turgut 《Otolaryngology--head and neck surgery》2006,135(1):52-55
OBJECTIVES: To investigate the role of Helicobacter pylori (H pylori) infection in laryngopharyngeal reflux (LPR). STUDY DESIGN: A prospective multidisciplinary clinical study. METHODS: Forty-four adult patients who applied to our ENT clinic with LPR symptoms were evaluated. Then these patients underwent upper gastrointestinal system endoscopy and double probe pH monitoring. In addition, during the endoscopy multiple biopsies from the stomach were obtained to detect H pylori. RESULTS: Results from 32 LPR positive patients were assessed (10 male and 22 female). There were no statistically significant differences between the presence of H pylori and sex, age, degree of gastritis and esophagitis, and also the number of reflux, fractional acid exposure time regarding proximal probe readings. Similarly for both proximal and distal probe readings, the average score of esophageal acid clearance was not statistically significant (P > 0.05). In addition, no statistically significant difference was found between the presence of H pylori and GERD (P > 0.05). CONCLUSIONS: The results of this study demonstrated that there is no relationship between gastric H pylori infection and LPR. EBM rating: B-3b. 相似文献
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Bharti Razdan Peter J. Marro Outi Tammela Rajiv Goel Om Prakash Mishra Maria Delivoria-Papadopoulos 《Brain research》1993,600(2):308-314
The effect of hypoxia on the structure and function of the synaptosomal membranes and myelin fraction (glial cells, neuronal cell bodies and axonal membranes) was investigated by measuring Na+,K+-ATPase activity and levels of lipid peroxidation products in cerebral cortical synaptosomal membranes and myelin fractions obtained from newborn piglets. Hypoxic hypoxia was induced and cerebral hypoxia was documented as a decrease in the ratio of phosphocreatine to inorganic phosphate (PCr/Oi) using31P-NMR spectroscopy. PCr/Pi decreased from baseline of2.93 ± 0.76to0.61 ± 0.36 during hypoxia. The synaptosomal membrane Na+,K+-ATPase activity decreased from a control value of56.6 ± 3.7to40.4 ± 6.0 μgmol Pi/mg protein/h during hypoxia. The level of conjugated dienes increased from zero (reference value) to4.5 ± 2.7 nmol/mg lipid and the level of fluorescent compounds increased from23.5 ± 2.2to92.6 ± 46.4 ng quinine sulfate/mg lipid in the synaptosomal membranes during hypoxia. No change in myelin fraction Na+,K+-ATPase activity or levels of lipid peroxidation products were noted. These data indicate that sunaptosomal membranes, rich in polyunsaturated fatty acids, are more susceptible to oxygen free radical mediated lipid peroxidative damage during hypoxia. 相似文献